408 research outputs found
Computationally efficient stratified flow wet angle correlation for high resolution simulations
n high resolution two-phase pipe flow simulations, such as slug capturing simulation for liquid-gas pipe flow, explicit calculation of stratified flow wet angle has been proposed to improve computational speed of simulations. Most phenomenological and approximate models for obtaining reliable predictions for stratified flow wet angle employ iterative methods or contain long explicit equations which reduce computational efficiency of these models in high-resolution simulations. Therefore, the aim of this study is to adapt a simple mathematical model for predicting stratified flow wet angle to achieve computationally efficient high-resolution liquid-gas pipe flow simulations
Reintegration of traumatic lower limb amputees into the society
Thirty male patients with an average age of 54.9 years responded to  questionnaires, interviews and clinical examination. Variables evaluated included mobility, selfcare, work, recreation, relationship with family members, and mechanism of injury. Among those working prior to amputation, 70% retufned to work within 12 months with 44.8% returning to their previous jobs. Seventy eight percent (78%) of respondents were completely independent at work, 92.4% felt there was no constraint to their mobility and two thirds of patients were satisfied with their adjustment. Traumatic amputees underwent successful physical rehabilitation. Vocational rehabilitation was less successful. However, factors that were positively associated with successful vocational rehabilitation included young age, strong family and social support
Steady state and transient liquid gas pipe flow models
Two-phase ow analyses are critical to successful design and operations of liquid-gas
pipe ow applications found in major industrial fields, such as petroleum, nuclear,
chemical, geothermal and space industries. Due to diffculties in obtaining analytical
solutions, approximate solutions have been applied to two-phase flows. However,
several limitations still exist, and categorised into three prediction models, namely:
ow regime, pressure gradient, and transient models.
Previous studies show that existing ow regime models and maps for horizontal
flows under-predicts transition from stratified to annular flow. Furthermore, there
is requirement to include criteria for identifying mist and plug flows in unified flow
regime model. In order to improve under-prediction in stratified to annular prediction,
nondimensional liquid lm height in original criterion is replaced with nondimensional
liquid holdup. This shifts stratified to annular transition line towards
higher gas superficial velocity thus improving prediction. Using experimental data
available in literature, a simple flow rate dependent criterion is proposed for identifying
the existence of mist flow. Two criteria are proposed for identifying plug flow
in horizontal and inclined flows. The first criterion is the exact criterion for identifying
bubble flow in vertical flows. The second criterion is also based on bubble
flow criterion but fitted to experimental data. Transition criterion for the existence
of dispersed-bubble flow is also proposed, based on stability of gas bubble in liquid
ow. These flow regime criteria are combined in a solution algorithm to obtain a
unified flow regime model, which has been verified using existing unified flow regime
models and map, and validated using experimental data.
Mechanistic or phenomenal methods are generally applied in predicting pressure
gradient in two-phase liquid-gas pipe flow. These methods relies on prior knowledge
of prevalent flow regime, and subsequent application of flow regime specific
pressure gradient model. This approach is susceptible to error should wrong flow
regime be selected. In order to overcome this problem, a Single Equation Two-Phase
Mechanistic (SETM) model is proposed. SETM is obtained by combining: liquidgas
momentum equations, existing and modified flow regime criteria, and new flow regime boundaries at the initiation and completion of transition to annular flow.
Thus, SETM implicitly determines pressure gradient and flow regime in liquid-gas
pipe flow, and also captures liquid-gas interface transition from at to curved interface.
SETM is applicable to all pipe inclination, and has been validated using
experimental data available in literature. Further, prediction of flow characteristic
features per ow regime, such as identified flow regime, liquid holdup in slug lm
region, ratio of slug regions, and apparent liquid heights, have been verified against
theoretical limits for different flow regimes. Alternative to SETM, modified homogeneous
pressure gradient model is also proposed for liquid-gas pipe flow. Existing
homogeneous models are applicable to dispersed bubble flow, and slug flow with
low or negligible liquid-gas slip. The modified homogeneous model is obtained by
correcting mixture fanny friction factor using error between experimental pressure
gradient and unmodified homogeneous pressure gradient; observed error is particularly
large at high liquid-gas slip values. The modified homogeneous model is
therefore applicable to all flow regimes, including stratified, annular, and mist flows.
The modified model has been verified against existing homogeneous model, and validated
using published experimental data.
Transient analysis is critical to liquid-gas pipe flow design. Rigorous analytical solution
is generally not available. Alternative solution method is full numerical solution
approach, which is subject to high demand on computational resources and time,
especially for long pipelines. Hence simplified transient methods are sort. Existing
simplified transient liquid-gas pipe flow models assume quasi-steady state conditions
for liquid-gas momentum equations, thus neglecting convective terms in the momentum
equations. The simplified transient liquid-gas pipe ow model proposed in this
study include: (a) transient liquid-gas continuity equations, (b) transient convective
terms of liquid-gas momentum equations, and (c) steady state pressure gradient
terms of liquid-gas momentum equations. The proposed transient model captures
gas and/or liquid flow variations at coarse pipe discretisation, and has been validated
against published experimental data and verified with a proprietary program
(OLGA)
ESL Curriculum: Oral Language Acquisition for Teaching Under-Privileged School-Aged Children of Hopeful Academy, Ibadan, Nigeria
This project is centered on the development of the ESL curriculum for teaching of oral language to under-privileged school-aged children of Hopeful Academy, Ibadan-Nigeria. It investigated the question âHow does Poverty impact the Oral Language Acquisition of English by School-Aged Children in Nigeria?â The content-based learning approach and the input-based approach served as useful guides in designing this ESL curriculum. The materials, activities, and units of this ESL Curriculum are mostly based on the Total Physical Response (TPR) from the WIDA English Language Proficiency standards. Childrenâs poor environments prevent them from being exposed to higher quantity and quality language learning environments. Learners do not always learn the same way since they are influenced by age, gender, and motivation. Learners need flexible tools and techniques like lesson warm-up, classroom discourse, pairing and grouping of students, and visuals to learn effectively. Learners learn differently when they are exposed to authentic materials as opposed to memorizing rules and vocabulary words. Future research may examine how Kids Youtube influences the oral language acquisition of children ages one to five
Border and Identity Negotiations: An Analysis of 19th Century Migrations in the U.S
Durch Archivrecherchen in Bibliotheken in den USA und Mexiko deckt Lim die verborgene Geschichte von Rassenkategorien und Reisen auf, die weitgehend aus dem nationalen Bewusstsein beider LĂ€nder gelöscht wurden, indem sie die Offenheit der Grenze von den 1880er Jahren bis zur ethnischen Differenzierung in den 1930er Jahren verfolgt. Durch Gesetze, Richtlinien und Erlasse erzwangen beide Staaten nationale und ârassischeâ Einheitlichkeit, was wiederum die FĂ€higkeit der Migranten einschrĂ€nkte, diese Grenzen zu ĂŒberschreiten. Doch die Einwanderer nutzten verschiedene Ăberlebenstechniken, z.B. die politischen Instrumente des Staates, nahmen unterschiedliche IdentitĂ€ten an und manövrierten ihre AnsprĂŒche auf StaatsbĂŒrgerschaft und Zugehörigkeit, je nachdem es ihre Situation zugelassen hat. Lims historische Darstellung lĂ€sst uns daher ĂŒber die herausfordernde Geschichte der multiethnischen Migration nachdenken. Sehr deutlich werden auch die Auswirkungen von Möglichkeitsstrukturen bei der EinschrĂ€nkung oder Ausweitung der MobilitĂ€t von Migranten.Through archival research in libraries in the U.S and Mexico, Lim reveals the hidden history of racial categories and journeys that have been largely erased from both countriesâ national consciousness by tracing the racial openness of the border from the 1880s to racial differentiation by the 1930s. Through laws, policies, and enactments, both states enforced national and racial uniformity, in turn, limiting migrantsâ ability to cross these boundaries. Yet the immigrants employed the stateâs political instruments, survival techniques, taking up different identities, maneuvering their claims to citizenship and belonging as different situations arise. Limâs historical account stimulates a reflection on the challenging history of multiracial migration and the influence of opportunity structures in limiting or expanding immigrantsâ mobility
Simplified Transient Two-Phase Model for Pipe Flow
Two-phase flow analyses are critical to successful design and operations of two-phase and multiphase pipe flow applications found in major industrial fields, such as petroleum, nuclear, chemical, geothermal and space industries. Due to difficulties in obtaining analytical transient solutions, approximate solutions have been applied to two-phase pipe flow. However, these approximate solutions neglect convective terms in two-phase Navier-Stokes equations. The aim of this current study was to develop transient tools to predict transient two-phase pipe flow. The objectives of this study were to develop a simplified transient model and to validate the proposed model with published experimental data. A simplified transient two-phase pipe flow model was obtained in this study by simplifying the two-phase Navier-Stokes equations. The simplified equations include: (i) a transient continuity equation of combined two-phase flow that includes two new dimensionless terms; (ii) transient two-phase momentum equations that account for convective terms only; and, (iii) a steady state pressure gradient
Determinant of Aquaculture Technologies Adoption among Fish-Farmers in Obafemi â Owode Local Government Area of Ogun State, Nigeria
The study was conducted to assess the determinant of aquaculture technologies adoption among fish-farmers in Obafemi – Owode local government area of Ogun State, Nigeria. Primary data were obtained from 224 fish farmers with an interview-schedule guide and field observation using simple random sampling and snow-balling sampling techniques during 2008 culture period. The study revealed that majority of the respondents were male (78.6%) within active age group of 41-50 years (47.0%), had primary education (51.0%), with household size of 7-8 persons (35.7%), farming as primary occupation (71.4%), fish farming experience of 3-4 years (40.0%) and belonged to fish farmers organization (51.4%). The major constraints in aquaculture were lack of access to appropriate land (31.4%), non-availability of micro-credits (97.1%), lateness in the supply of technological packages (75%), lack of infrastructural facilities (75%) and spatial factors to extension services and inputs (67.1%). The result of chi-square analysis showed that only sex (0.672, p<0.01) and extension agents (0.060; p<0.01) had significant association between socio-economic information variables and aquaculture technologies adoption. Based on the findings of this study, the following were therefore recommended: In an enterprise where a large proportion of the fish farmers were literate, adoption of disseminated improved innovation by extension agents will be embraced, high proximity to extension and communication services as well as aquaculture inputs will be enhanced if farmers formed themselves into cooperative societies, provision of rural infrastructures, as well as credit facilities should be provided by government. Participatory development of technologies between researchers and farmers are essential factors for adoption of new fish farming technologies.  
Assessment of Microfinance Institutions as Poverty Reduction Mechanism in Nigeria
Microfinance Institutions are intended to bridge the financial gap usually created by the dearth of capital created by the inability of the conventional banks to support the Small and Medium Scale Enterprises in the country. This has however provided the compelling reasons why issues relating to Microfinance Institutions have to be taken more seriously in Nigeria than ever before.This paper therefore focused on the identification of the causes of poverty in Nigeria and the extent to which microfinance institutions have helped in reducing poverty in the Nigerian economic development.. The researcher used Chi- square, Analysis of Variance (ANOVA) and the method of regression analysis for investigating the contribution made by the microfinance institutions to poverty reduction in the Nigerian context. The study revealed that exclusion of the poor from the financial system seriously contributed to their inability to participate in the development process. Equally with no access to funding therefore, the household finds in extremely difficult to take advantage of economic opportunities to improve their lots and their children and protect them against financial imbalances, thereby making them to be permanently within the vicious circle of poverty. The analysis revealed that increase microcredit finances drastically reduced poverty level in Nigeria and also the poverty index. The study also revealed that microfinance institutions contributes most considerably to the empowerment of the masses, majority of whom were women, rural dwellers and this has translated in business and financial development in Nigeria. Keywords: Microfinance, Financial empowerment, Entrepreneurial functions, Development Finance Institutions(DFIs), Poverty
Empirical Analysis of the Effect of Accountability on Budget Implementation in Ondo State Nigeria
The paper aimed at analyzing the effect of accountability on budget implementation in Nigeria using Ondo State Ministry of Finance as a case study. The paper adopts a survey design and secondary data which were obtained from statistical bulletin of Ministry of Finance. The time series data covers the period of eight (8) years from 2007-2014. The data was analyzed using ordinary least square (OLS) and Augmented Dickey Fuller (ADF) unit root test with the aid of E-view 7 Software Statistical package. The findings reveal that the coefficient of multiple determination is low in explaining the annual approved budget estimates, besides, the formulated model does not show a good fit of the total approved budget estimates due to some unforeseen occurrences that affects the measure of accountability during budget implementation. This was further justified by the t-test and F-test results. The paper recommended the use of accurate data which will be predicated on the performance of past budgets. Also, there is a need for strict observance of budget discipline by the executive to guide against extra-budgetary spending
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